It is located between the cylinder head and the exhaust manifold; it prevents exhaust gases from escaping.
Cummins specifies the primary use for 10-liter L10 engines; aftermarket catalogs extend the application to the M11, ISM, and QSM families. Final compatibility should be verified using the engine’s serial number.
It creates a seal between two engine surfaces, preventing oil or other fluid leaks at the mounting point. Cummins specifies its primary use on non-certified 11-liter M11 engines; you can also find them on L10, ISM, and QSM engines.
Exact compatibility must be verified using the ESN, as the location and configuration may vary.